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### _Why are the changes needed?_
### Description
`ServiceDiscovery` contains `discovery` and `zookeeper` part, `ServiceDiscovery` should only has one responsibility.

### _How was this patch tested?_
- [ ] Add some test cases that check the changes thoroughly including negative and positive cases if possible
- [ ] Add screenshots for manual tests if appropriate
- [ ] [Run test](https://kyuubi.readthedocs.io/en/latest/develop_tools/testing.html#running-tests) locally before make a pull request
Closes#931 from timothy65535/ky-930.
Closes#930
29d48921 [timothy65535] Add ZooKeeperClientProvider
17fbe5a2 [timothy65535] [KYUUBI #930] Extract the zookeeper part from ServiceDiscovery
Authored-by: timothy65535 <timothy65535@163.com>
Signed-off-by: Cheng Pan <chengpan@apache.org>